Mineralogy samples from the
Earth's mantle are some of the rarest and most difficult geologic materials for
educators, collectors and the scientific community to acquire. The samples
listed are offered on a first-come, first serve basis and guaranteed to be
exactly as described. All major credit cards accepted including PayPal. Checks
are welcome.

Natural Diamonds from
Rare Localities

These are unusual and rare
localities. All images were taken of the specimens being offered.

Carbonado or "black" diamonds, are exotic diamonds found in
Brazil and the Central African Republic. They are unusual for being the color
of charcoal, sometimes having a frothy texture. These diamonds can also have a
face that looks like melted glass. A research team led by Dr. Stephen Haggerty
of Florida International University in Miami has presented a new study that
these "stones" were brought to Earth by an asteroid billions of years
ago. The findings were published online in the journal "Astrophysical
Journal Letters" on December 20, 2006.

The scientists exposed polished pieces of these stones, now known as carbonado
diamonds, to extremely intense infrared light. The test revealed the presence
of many hydrogen-carbon bonds, indicating that the diamonds probably formed in
a hydrogen-rich environment-such as that found in space. The diamonds also
showed strong similarities to tiny nanodiamonds, which are frequently found in
meteorites. Astrophysicists have developed theories predicting that
nanodiamonds form easily in the stellar explosions called supernovas, which
scatter debris through interstellar space. Haggerty's research indicates that
the deposits in the Central African Republic and Brazil, came from the impact
of a diamond-rich asteroid millions of years ago, when South America and Africa
were joined. So even though the two diamond fields are now thousands of miles
apart, they're remnants of a single, original deposit. Haggerty estimated that
the asteroid must have been about half a mile (one kilometer) in diameter.

The unusual bubbles seen in specimens of carbonados probably came from fizzing
gases when the diamonds were forming, Haggerty added. This adds further
credence to the extraterrestrial origin theory, since conventional diamonds
form under immense pressure deep beneath the Earth's crust, where gas bubbles
simply couldn't form. Carbonado diamonds also contain a mineral called
osborneite, which has been found only in meteorites and comet dust recovered by
the recent Stardust mission. Additionally, adding to the evidence for an
extra-terrestrial origin, carbonado diamonds have never been reported among any
of the other 600 tons of "conventional" diamonds mined, sorted,
graded, traded, cut, and polished in the last century.